U.S. Pat. No. 4,563,836 (Woodruff et al., 1986) refers to an insect feeding station having a unitary base and optionally a partially or totally transparent cover. This patent teaches the use of a transparent cover in conjunction with a contrasting color base portion under the poison to make the poison contained in a central feeding area visible through the transparent cover.
U.S. Pat. No. 4,485,582 (Morris, 1984) relates to an insect feeding station having a base and transparent cover where the poison compartment has a contrasting luminous color under the poison to make removal of poison easily detectable, that is, the floor liner compartment of the poison compartment is coated with a contrasting colored layer before affixing the bait.
U.S. Pat. No. 4,894,947 (Brandli, 1990) relates to an insect feeding station having a central poison area, guide walls leading from the periphery of the station to the central poison area and a cover optionally having a transparent means to view the poison area. The transparency of the cover, or portion or section thereof, permits viewing of the poison compartment which has a contrasting luminous color under the poison to make detection of removal of the poison bait easily apparent.
U.S. Pat. No. 5,048,225 (Brandli, 1991) relates to an insect feeding station having a central poison area with a cover which is optionally transparent to view the poison area. The poison compartment may have a contrasting luminous color under the poison to make detection of the consumption of poison by the insects easily detectable through the transparent cover.
Such bait stations provide transparent covers for their respective bait stations that allow bait to be easily visible. In the prior art devices, the insects enter the bait stations containing the poison bait and actively feed therein consuming the bait. However, the prior art devices are generally of a construction that the material for the covers will present difficulties in viewing the interior so that it is not readily ascertainable whether insects remain in the device or how much of the poison bait has been consumed.
In other prior art devices, viewing of the insects and bait is through a transparent cover. However in the transparent covers of the prior art, the cover is transparent to light of all wavelengths. Unfortunately, the German cockroach [Blattella germanica (L.)] is a nocturnal or light-avoiding insect. Many insects, including the German cockroach in particular, are nocturnal feeders. German cockroaches will more readily feed in dark environments than in lit environments. German cockroaches have been observed to encounter food under lit conditions and to continue to seek dark shelter, rather than immediately consume the food that may be otherwise readily available. Feeding tests have indicated that German cockroaches use insect bait stations as harborages under general lighting conditions, returning to other harborages either when the station is disturbed or not under dark conditions. Bait stations have been found to contain dead cockroaches within the station, even though the active ingredient takes at least one day to kill the insect, because the cockroaches declined to leave the safety of the dark bait station when the exterior is under lit conditions.
It is reported by Koehler et al. in Ann. Entomol. Soc. M. 80:820-822 (1987) that the German cockroach has color vision, that is, the German cockroach sees light with its compound eyes, and receives light through ocelli and dermal photoreceptors as well. The German cockroach is a primary domestic cockroach pest species. Koehler et al. has determined the spectral sensitivity of the German cockroach compound eye and determined the influence on local motor activity.
The work of Koehler et al. also has shown significantly higher startle response activity under light of wavelengths of shorter than 600 nanometers (nm). In addition, it was shown that the German cockroach compound eye is not sensitive to light wavelengths greater than 600 nm.
It is now therefore an object of this invention to provide an insect feeding station with a transparent cover which will transmit light of wavelengths greater than 600 nm. Such transparent bait station covers will provide bait stations which will have significantly higher cockroach feeding under lighted conditions, than do bait stations with covers that transmit light at all wavelengths, including lower wavelengths.
It is an object of this invention to provide a translucent cover for an insect feeding station wherein the light transmitted therethrough is of selected wavelengths which will result in higher bait consumption and insect mortality over those bait stations having transparent covers.
It is an object of this invention to provide a method of increasing the feeding of nocturnal feeding insects under lit conditions by employing a bait station having attached thereto a cover of a material through which transmitted light is of selected wavelengths not perceptible to the insects.
It is yet a further object of this invention to provide a method of inspecting an insect feeding station without disturbing any insects therein by placing on the feeding station a cover made of material through which transmitted light is of selected wavelengths not perceptible to the insect.
A further object of the present invention is to provide an improved insect feeding station cover which will allow the bait to be inspected without reducing the effectiveness of the bait station for insect feeding.
Another object of the present invention is to provide an insect feeding station cover which will allow the bait to be inspected without reducing the attractiveness of the bait station for insect feeding.
A still further object of the present invention is to provide an insect feeding station cover which will be desirable for German cockroaches to seek refuge therein under lit conditions.